Europe fends off alien species

To help decision makers mitigate the consequence of alien plant and animal invasion, an EU-wide database maintains a black list of these unwelcome biological invaders.

It may look incredibly innocent, but the harlequin ladybird, a stowaway onboard fruit and flower consignments from Asia, is on a ‘most unwanted’ list. Indeed, it falls within the category of some of Europe’s most destructive and threatening non-native settlers. Aiming to stem the tide against such unwelcome biological invaders by documenting them, the DAISIE online database was recently updated to include over 1,000 additional species.

“DAISIE covers the gamut from marine, aquatic and terrestrial environments, including fungi, insects and plants right through to fish, birds and mammals,” says Helen Roy, Ecological Entomologist at the UK’s Centre for Ecology & Hydrology (CEH), in Wallingford, and the project co-ordinator. “We now have data on over 12,000 alien species in Europe.” Previously funded by the EU, the ongoing project is now being backed by CEH and the Sciex programme, which supports scientific exchange between Switzerland and the new member states of the European Union.

About 10% of these non-natives are described as invasive due to their aggressive impact in altering ecosystems and pushing out their native counterparts. The deceptively pretty little harlequin ladybird, for example, is guilty of squeezing out other insects sharing its taste for sap-sucking insects. Invasive species are among the biggest threats to biodiversity globally. Moreover, their damage and control bill costs Europe an estimated €12.5 billion annually. Harlequin ladybird infestation, for example, poses threat to householders and damages fruit crops.

The database is designed to provide decision makers with the tools to anticipate the threat. “DAISIE can help policy makers, researchers and NGOs to understand where alien species are coming from, which are most likely to become invasive and what control strategies could prove effective,” Roy says.

It is more suitable for basic education purposes or those exploring trends across species, over time or by region rather than specialists looking for deep information on individual invasive species, says Alexander Dayes, managing director of Japanese Knotweed Solutions Ltd, an invasive weed control company, based in Manchester, UK. “We don’t use it nor am I aware of anyone else in our industry who does,” Dayes says.

However, he believes it could be a great resource for local authorities. “This could include educating community groups to operate an alert system for non-native species previously unseen in their area or mobilising voluntary teams to clear invasive weeds from large tracts of common land.” It appears to have played a positive role. “Public awareness has improved, but increased international trade and climate change are posing new risks,” points out Roy.

It could therefore help anticipating further threat developing on an ongoing basis. “Its pan-European coverage means that it can provide an early warning system for invasive threats on the horizon,” comments Colette O'Flynn. As manager of Ireland’s National Biodiversity Data Centre, based in Waterford, her role includes contributing to national action plans for responding to invasive species threats. She warns, however, “nothing remains static in the world of invasive species, so DAISIE will only stay relevant if it is continually updated.”